I did do a bleed after the master cylinder was replaced but I didn't see any air coming out any of the calipers. I was expecting some air since both master cylinder lines were disconnected. I probably should just pump some more brake fluid through the system since the ABS adds so much more tubing. Just wanted to see if an ABS problem could have caused the initial loss of brake operation but it was probably the master cylinder. I may have duplicated the initial problem symptoms by introducing air in the lines.